1. Field of the Invention
The present invention relates to an optical receiver module and an optical transmitter module.
2. Description of the Related Art
In general, an optical receiver module and an optical transmitter module used in optical communications or the like include, as well as a light receiving portion and a light emitting portion, various lenses for guiding light from an optical fiber to the light receiving portion or for guiding light from a transmitting portion to an optical fiber, respectively. In Japanese Patent Application Laid-open No. Hei 05-224101, among such optical receiver modules and optical transmitter modules, there is disclosed a configuration of a semiconductor light receiving device as an optical receiver module.
Further, the optical receiver module and the optical transmitter module exhibit a loss due to back reflection light, which is called an optical return loss (ORL), and regarding suppression of this loss, Japanese Patent Application Laid-open No. Hei 10-268164 discloses a configuration of arranging a light receiving portion surface obliquely with respect to a light beam from a condenser lens, and Japanese Utility Model Examined Publication No. Sho 62-006707 and Japanese Patent Application Laid-open No. 2013-200550 disclose configurations of arranging a light receiving portion with its axis shifted with respect to a condenser lens.